lib/gnutls_global.c

   1 /*
   2  * Copyright (C) 2001-2012 Free Software Foundation, Inc.
   3  *
   4  * Author: Nikos Mavrogiannopoulos
   5  *
   6  * This file is part of GnuTLS.
   7  *
   8  * The GnuTLS is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public License
  10  * as published by the Free Software Foundation; either version 3 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public License
  19  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20  *
  21  */
  22
  23 #include <gnutls_int.h>
  24 #include <gnutls_errors.h>
  25 #include <libtasn1.h>
  26 #include <gnutls_dh.h>
  27 #include <random.h>
  28 #include <gnutls/pkcs11.h>
  29
  30 #include <gnutls_extensions.h>  /* for _gnutls_ext_init */
  31 #include <locks.h>
  32 #include <system.h>
  33 #include <accelerated/cryptodev.h>
  34 #include <accelerated/accelerated.h>
  35
  36 #include "sockets.h"
  37 #include "gettext.h"
  38
  39 /* Minimum library versions we accept. */
  40 #define GNUTLS_MIN_LIBTASN1_VERSION "0.3.4"
  41
  42 /* created by asn1c */
  43 extern const ASN1_ARRAY_TYPE gnutls_asn1_tab[];
  44 extern const ASN1_ARRAY_TYPE pkix_asn1_tab[];
  45 extern void *_gnutls_file_mutex;
  46
  47 ASN1_TYPE _gnutls_pkix1_asn;
  48 ASN1_TYPE _gnutls_gnutls_asn;
  49
  50 gnutls_log_func _gnutls_log_func;
  51 gnutls_audit_log_func _gnutls_audit_log_func;
  52 int _gnutls_log_level = 0;      /* default log level */
  53
  54 /**
  55  * gnutls_global_set_log_function:
  56  * @log_func: it's a log function
  57  *
  58  * This is the function where you set the logging function gnutls is
  59  * going to use.  This function only accepts a character array.
  60  * Normally you may not use this function since it is only used for
  61  * debugging purposes.
  62  *
  63  * @gnutls_log_func is of the form,
  64  * void (*gnutls_log_func)( int level, const char*);
  65  **/
  66 void
  67 gnutls_global_set_log_function (gnutls_log_func log_func)
  68 {
  69   _gnutls_log_func = log_func;
  70 }
  71
  72 /**
  73  * gnutls_global_set_audit_log_function:
  74  * @log_func: it is the audit log function
  75  *
  76  * This is the function where you set the logging function gnutls is
  77  * going to use.  This is different from gnutls_global_set_log_function()
  78  * because it will report the session of the event if any. Note that
  79  * that session might be null if there is no corresponding TLS session.
  80  *
  81  * @gnutls_audit_log_func is of the form,
  82  * void (*gnutls_audit_log_func)( gnutls_session_t, int level, const char*);
  83  *
  84  * Since: 3.0
  85  **/
  86 void
  87 gnutls_global_set_audit_log_function (gnutls_audit_log_func log_func)
  88 {
  89   _gnutls_audit_log_func = log_func;
  90 }
  91
  92 /**
  93  * gnutls_global_set_time_function:
  94  * @time_func: it's the system time function, a gnutls_time_func() callback.
  95  *
  96  * This is the function where you can override the default system time
  97  * function.  The application provided function should behave the same
  98  * as the standard function.
  99  *
 100  * Since: 2.12.0
 101  **/
 102 void
 103 gnutls_global_set_time_function (gnutls_time_func time_func)
 104 {
 105   gnutls_time = time_func;
 106 }
 107
 108 /**
 109  * gnutls_global_set_log_level:
 110  * @level: it's an integer from 0 to 9.
 111  *
 112  * This is the function that allows you to set the log level.  The
 113  * level is an integer between 0 and 9.  Higher values mean more
 114  * verbosity. The default value is 0.  Larger values should only be
 115  * used with care, since they may reveal sensitive information.
 116  *
 117  * Use a log level over 10 to enable all debugging options.
 118  **/
 119 void
 120 gnutls_global_set_log_level (int level)
 121 {
 122   _gnutls_log_level = level;
 123 }
 124
 125 /**
 126  * gnutls_global_set_mem_functions:
 127  * @alloc_func: it's the default memory allocation function. Like malloc().
 128  * @secure_alloc_func: This is the memory allocation function that will be used for sensitive data.
 129  * @is_secure_func: a function that returns 0 if the memory given is not secure. May be NULL.
 130  * @realloc_func: A realloc function
 131  * @free_func: The function that frees allocated data. Must accept a NULL pointer.
 132  *
 133  * This is the function where you set the memory allocation functions
 134  * gnutls is going to use. By default the libc's allocation functions
 135  * (malloc(), free()), are used by gnutls, to allocate both sensitive
 136  * and not sensitive data.  This function is provided to set the
 137  * memory allocation functions to something other than the defaults
 138  *
 139  * This function must be called before gnutls_global_init() is called.
 140  * This function is not thread safe.
 141  **/
 142 void
 143 gnutls_global_set_mem_functions (gnutls_alloc_function alloc_func,
 144                                  gnutls_alloc_function secure_alloc_func,
 145                                  gnutls_is_secure_function is_secure_func,
 146                                  gnutls_realloc_function realloc_func,
 147                                  gnutls_free_function free_func)
 148 {
 149   gnutls_secure_malloc = secure_alloc_func;
 150   gnutls_malloc = alloc_func;
 151   gnutls_realloc = realloc_func;
 152   gnutls_free = free_func;
 153
 154   /* if using the libc's default malloc
 155    * use libc's calloc as well.
 156    */
 157   if (gnutls_malloc == malloc)
 158     {
 159       gnutls_calloc = calloc;
 160     }
 161   else
 162     {                           /* use the included ones */
 163       gnutls_calloc = _gnutls_calloc;
 164     }
 165   gnutls_strdup = _gnutls_strdup;
 166
 167 }
 168
 169 static int _gnutls_init = 0;
 170
 171 /**
 172  * gnutls_global_init:
 173  *
 174  * This function initializes the global data to defaults.
 175  * In order to free resources you may call gnutls_global_deinit()
 176  * when gnutls usage is no longer needed.
 177  *
 178  * Note that this function will also initialize the underlying crypto
 179  * backend, if it has not been initialized before.
 180  *
 181  * This function increments a global counter, so that
 182  * gnutls_global_deinit() only releases resources when it has been
 183  * called as many times as gnutls_global_init().  This is useful when
 184  * GnuTLS is used by more than one library in an application.  This
 185  * function can be called many times, but will only do something the
 186  * first time.
 187  *
 188  * Note!  This function is not thread safe.  If two threads call this
 189  * function simultaneously, they can cause a race between checking
 190  * the global counter and incrementing it, causing both threads to
 191  * execute the library initialization code.  That would lead to a
 192  * memory leak.  To handle this, your application could invoke this
 193  * function after aquiring a thread mutex.  To ignore the potential
 194  * memory leak is also an option.
 195  *
 196  * Returns: On success, %GNUTLS_E_SUCCESS (0) is returned,
 197  *   otherwise a negative error code is returned.
 198  **/
 199 int
 200 gnutls_global_init (void)
 201 {
 202   int result = 0;
 203   int res;
 204
 205   if (_gnutls_init++)
 206     goto out;
 207
 208   if (gl_sockets_startup (SOCKETS_1_1))
 209     return gnutls_assert_val(GNUTLS_E_FILE_ERROR);
 210
 211   bindtextdomain (PACKAGE, LOCALEDIR);
 212
 213   res = gnutls_crypto_init ();
 214   if (res != 0)
 215     {
 216       gnutls_assert ();
 217       return GNUTLS_E_CRYPTO_INIT_FAILED;
 218     }
 219
 220   _gnutls_register_accel_crypto();
 221
 222   /* initialize ASN.1 parser
 223    * This should not deal with files in the final
 224    * version.
 225    */
 226   if (asn1_check_version (GNUTLS_MIN_LIBTASN1_VERSION) == NULL)
 227     {
 228       gnutls_assert ();
 229       _gnutls_debug_log ("Checking for libtasn1 failed: %s < %s\n",
 230                          asn1_check_version (NULL),
 231                          GNUTLS_MIN_LIBTASN1_VERSION);
 232       return GNUTLS_E_INCOMPATIBLE_LIBTASN1_LIBRARY;
 233     }
 234
 235   res = asn1_array2tree (pkix_asn1_tab, &_gnutls_pkix1_asn, NULL);
 236   if (res != ASN1_SUCCESS)
 237     {
 238       result = _gnutls_asn2err (res);
 239       goto out;
 240     }
 241
 242   res = asn1_array2tree (gnutls_asn1_tab, &_gnutls_gnutls_asn, NULL);
 243   if (res != ASN1_SUCCESS)
 244     {
 245       asn1_delete_structure (&_gnutls_pkix1_asn);
 246       result = _gnutls_asn2err (res);
 247       goto out;
 248     }
 249
 250   /* Initialize the random generator */
 251   result = _gnutls_rnd_init ();
 252   if (result < 0)
 253     {
 254       gnutls_assert ();
 255       goto out;
 256     }
 257
 258   /* Initialize the default TLS extensions */
 259   result = _gnutls_ext_init ();
 260   if (result < 0)
 261     {
 262       gnutls_assert ();
 263       goto out;
 264     }
 265
 266   result = gnutls_mutex_init(&_gnutls_file_mutex);
 267   if (result < 0)
 268     {
 269       gnutls_assert();
 270       goto out;
 271     }
 272
 273 #ifdef ENABLE_PKCS11
 274   gnutls_pkcs11_init (GNUTLS_PKCS11_FLAG_AUTO, NULL);
 275 #endif
 276
 277   _gnutls_cryptodev_init ();
 278
 279 out:
 280   return result;
 281 }
 282
 283 /**
 284  * gnutls_global_deinit:
 285  *
 286  * This function deinitializes the global data, that were initialized
 287  * using gnutls_global_init().
 288  *
 289  * Note!  This function is not thread safe.  See the discussion for
 290  * gnutls_global_init() for more information.
 291  **/
 292 void
 293 gnutls_global_deinit (void)
 294 {
 295   if (_gnutls_init == 1)
 296     {
 297       gl_sockets_cleanup ();
 298       _gnutls_rnd_deinit ();
 299       _gnutls_ext_deinit ();
 300       asn1_delete_structure (&_gnutls_gnutls_asn);
 301       asn1_delete_structure (&_gnutls_pkix1_asn);
 302       _gnutls_crypto_deregister ();
 303       _gnutls_cryptodev_deinit ();
 304 #ifdef ENABLE_PKCS11
 305       gnutls_pkcs11_deinit ();
 306 #endif
 307       gnutls_mutex_deinit(&_gnutls_file_mutex);
 308     }
 309   _gnutls_init--;
 310 }
 311
 312 /* These functions should be elsewere. Kept here for
 313  * historical reasons.
 314  */
 315
 316
 317 /**
 318  * gnutls_check_version:
 319  * @req_version: version string to compare with, or %NULL.
 320  *
 321  * Check GnuTLS Library version.
 322  *
 323  * See %GNUTLS_VERSION for a suitable @req_version string.
 324  *
 325  * Returns: Check that the version of the library is at
 326  *   minimum the one given as a string in @req_version and return the
 327  *   actual version string of the library; return %NULL if the
 328  *   condition is not met.  If %NULL is passed to this function no
 329  *   check is done and only the version string is returned.
 330   **/
 331 const char *
 332 gnutls_check_version (const char *req_version)
 333 {
 334   if (!req_version || strverscmp (req_version, VERSION) <= 0)
 335     return VERSION;
 336
 337   return NULL;
 338 }